Primaloft Eco is around ~70% as warm as primaloft one for a given weight of insulation (67%-75% depending on moisture).
So for identical jackets/vests with just different insulation the Nano-puff will feel warmer. Design, materials, construction, and fit will all contribute to warmth differently.
As others have mentioned though these fabrics are less durable than some climashield products (primaloft focuses on a technology that values warmth over durability while climashield reverses the priority of those constraints). There are also a lot of proprietary insulations out there that have really advanced (Dane at coldthistle blog is convinced MBs exceloft is the warmest out there per weight and he's got a ton of field experience with synthetics). Both the MB exceloft and MHW Thermic micro are supposed to be seeing major improvements to their warmth/weight this upcoming year while increasing durability in the process.
Basically the point is that weight of insulation is still a good general rule of thumb. Any 60g/m layer will suffice for conditions where you want 60g/m warmth. Some may be a little lighter or warmer than others but you'll be adequately (not necessarily comfortably) warm for the conditions.